[Marmot]

Originally Posted by AMG

Not when you translate it into range.

You figure those boats will do a lot of long range cruising?

They are made for speed, not for tankering enough fuel to get anywhere.

That is where designers (stylists) get it so wrong. They forget or don't know that weight is the antithesis of speed and "high performance" for the kind of boats that would use this kind of drive. If they want speed they can't tanker a large load of fuel, high power burns a lot of fuel so the range must be short. If they want range and speed those drives can't deliver enough power to do both without using herds of engines and lower units. The boat would look like a sea urchin and the drag would be all out of proportion.

There are lighter more efficient means to power a 100 foot hull at high speeds than with 4 or 6 engines and drives sticking out all over the bottom.

Repeat after me: cost benefit cost benefit

[AMG]

Originally Posted by Marmot

And there are lighter more efficient means to power that kind of hull.

You are welcome to show the better options, I will soon design a fast 75-footer...

[yachtbrokerguy]

[Marmot, the IPS is for boats that otherwise have shafts and rudders. They are not competing with outdrives, which by the way can also have joystick steering.)


I have a listing on an Island Pilot 395, a fast trawler type of small boat with Volvo diesels and outdrives. This boat is smaller than most of my listings, but I thought it would make a great boat for use in the Bahamas, the Florida Keys, the west coast of Florida or anywhere else with a lot of skinny water. This model was first built with outdrives and then with IPS, and can be purchased either way. Only a 3'2" draft, and if you run into a 3' spot, the outdrive can tilt up, a big advantage over the IPS.

Two or three years ago a boat of this size with outdrives would be very difficult to sell, but with all the press on IPS, the outdrives look better. I have described in the listing that the Volvo duo prop outdrives are the PRECURSER to the IPS, the technology is not really too far different.

[AMG]

Originally Posted by yachtbrokerguy

I have described in the listing that the Volvo duo prop outdrives are the PRECURSER to the IPS, the technology is not really too far different.

You are right in the timeline, but as I said, IPS is not to replace outdrives. Boats where you have both as an option, usually sell more outdrives. They give you a better speed/mileage and also have props for higher speeds.

We have used Aquamatic on all boats up to 40 feet, with top speeds near 50 knots. On our new 54´we will try IPS in twin and triple installations, but the props are only allowing a top speed of 43 knots. Perhaps Cat/Zeus have faster options but I have not found out yet.

Whatever, there are no standard outdrives that can take the torque of a 575 hp diesel as far as I know.

[Marmot]

Originally Posted by AMG

Whatever, there are no standard outdrives that can take the torque of a 575 hp diesel as far as I know.

http://www.thrustmastertexas.com/pro...sionUnits.html

[FISHTIGUA]

Most members know I like IPS but we are now doing a major rebuild of a very early installation.

The seals had let go and salt water was left to sit in the drive while the boat was for sale. Volvo are covering the costs and these are riseing very fast.

Each part of the rebuild we delve deeper into the drive, the more corrosion we have found. Pitting has traveled right up to the main ring, thus everything except the shafts and outerbody have to be changed.

This all may sound major money but I've ordered the following yesterday

1 X Gearbox for a Sidepower 55 bowthruster £430

1 X Gearbox for a Bukh 20hp sailboat engine £910

1 X Gearbox for a Volvo 122D , get this, £8750 without oil cooler

(Not sure what the rate of $ exchange is today, about 1 to 1.46 I think)

The IPS is now sounding not too bad against that little lot, costwise, for a rebuild. £3000 for a complete job. The costs with a DPH is not that much lower and more often (bi-annually sometimes).

As AMG says, how else do you put 500hp down without shafts?

As a small aside, Sidepower are now offering a sternthruster that sits between DPH drives, that should help a bit on larger boats.

[Marmot]

Originally Posted by AMG

You are welcome to show the better options, I will soon design a fast 75-footer...

You can probably sell the TBODs (ThruBottomOutDrives) to someone who can justify it just because no one else on his block has one.

But if you are really asking for better options for a 75 foot fast boat, you have already been shown them ... jet drives for a fast boat or surface piercing drives for a really fast boat.

Now you are welcome to show us how you can get enough power to move a 75 foot boat "fast" using TBODs without installing a half dozen of the silly things.

Of course it doesn't cost a stylist anything to "design" a whole herd of powerplants into a computer rendering but some poor schmuck has to pay the lifecycle costs of the hardware.

Repeat after me: cost benefit ... cost benefit ... cost benefit

[AMG]

Originally Posted by Marmot

... jet drives for a fast boat or surface piercing drives for a really fast boat.

OK, but people are not buying them because of several reasons. But anyone who has tried an IPS-boat want to have it, especially women like them.

Last but not least, a boat designer have to create a boat that sells. If it is not working or not selling, I am out of job.

[Marmot]

Originally Posted by AMG

Last but not least, a boat designer have to create a boat that sells. If it is not working or not selling, I am out of job.

I have to give you full marks for honesty.

Both you and the future (probably short term) owner are the victims of marketing hype.

[AMG]

Originally Posted by Marmot

Now you are welcome to show us how you can get enough power to move a 75 foot boat "fast" using TBODs without installing a half dozen of the silly things.

I hope to install twin or triple IPS III with D13:s of 1.200 hp each or so...? That would move my new hull pretty fast.

[rip728]

Ok guys, maybe I am wrong. But Paul Spencer seems to be going forward with this type system (I just can't see jets on a sportfish), Lazzara has a few models now (a 92' yacht with yes 4 IPS 900's that cost less than twin 1,800HP shaft versions and burns less than 100 GPH at a 25+ knot cruise), Freedom Yachts has a triple IPS 2 sportfish advertised and I am pretty sure Donald Blount is into this since he reviews all IPS potentials I am told.
I think these fellas have been around the block a time or two and understand their markets. Lazzara has built more than 15 75 LSX's I believe. Max fuel burn on those by the way is 88 GPH, since each little D6 can only burn 22 GPH. Pretty thrifty I would say, and they seem to be selling pretty well. I don't have much info on the 76' with triple ZEUS they announced at Miami. I don't think it is in full production yet.

[Highlander]

For 10 years now, I have been running a dinosaur, a jet boat with no electronics in the drive system. Steering is hydraulic as well as the bucket (reverse thrust) controlls. I love it! I dare anyone to do better with any kind of joystick!
What happens to IPS or other systems when the computer goes ZAP! ?

I happened to be at Little Harbor when they were testing an early joystick (mandated by Hinckley, the new owners) , the first trial failed when they threw some water on it. The second time they built a back up system that worked with hard wired toggle switches. The guy who taught me how to run a jet, was there and he docked the boat using only the switches and the hydraulic steering.

Do any of these new systems have a backup plan?

[AMG]

Originally Posted by Highlander

Do any of these new systems have a backup plan?

IPS has a "take-me-home" function, but not a parallell system. (As far as I know).

[Blair]

Highlander mentions about reliability of joy sticks for jets in particular - Hamilton has the Mouse Boat version for their units and one would expect that Hinkley's have since adopted the latest stuff.

As far as I am aware the systems that Hamilton Jet offers derived from the very sophisticated control units developed for larger craft with multiple big jets - crew boats, ferries and military applications for example. Apparently very reliable and proven. I understand they still have the levers for manual operation with the wheel but I am not sure whether twin or more units could then be steered independently and in opposition to each other for dynamic manouvering (in conjunction with bow thrusters in some cases) that the electronic function obviously offers. Basically though, you would not be dead in the water and unable to steer etc if a failure occurred.

Salthouse Marine here has launched a couple of 65' game boats with quad IPS's and has orders for more - mainly from Australia. Flat out is about 32 knots and cruise late 20's. Seem to have caught a keen market with them. Mind you, in our typical sea conditions in NZ (and Australia perhaps) few would want to try and travel at 45 knots! Salthouse are looking at the new larger HP IPS versions in triple configuration for some new builds too. Worth a look at their website perhaps.

[FISHTIGUA]

Now that Volvo have sold 10,000 IPS units and we have rebuilt our first one, I have to tell you how it was re-installed.

We have a 75 ton Travellift, so we had to tilt the 42 foot cruiser over a few degrees so that the deadrise was equal with the ground for a straight lift up. It looked quite spectacular and wrong. It went straight in, nice job.

Of course the Engineer put his toolbag on top of the genset box ,so as the hull was tiltted, all his tools slid down the back and into the bilge.

As any of you know, Volvo Saildrives have a rubber ring that seals from the box to the drive and sometimes saltwater can get inside and start to rot underneath the ring. IPS is no different. Thus an installation change has been made, check with your dealer.

So,all in all, a rebuilt IPS takes about 4 more hours to do over an outdrive but is a lot quicker to put back with a good, big Travellift.

Fish